drm/i915: move clock gating functionality into intel_pm module

This moves the clock gating-related functions into intel_pm module.

Also, please note that we do change the function type from static to
non-static in this patch for the move, to prevent breaking bisecting with
non-working intermediate commit. Those are returned back to static form in
the following patch which setups a generic PM initialization function,
which was split into a different one to simplify review.

v2: rebase on top of latest drm-intel-next-queued to incorporate all the
changes that went there meanwhile.

Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 370 insertions, 354 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 4fb1982..dec67aa 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1515,7 +1515,7 @@ static void intel_disable_pipe(struct drm_i915_private *dev_priv,
  * Plane regs are double buffered, going from enabled->disabled needs a
  * trigger in order to latch.  The display address reg provides this.
  */
-static void intel_flush_display_plane(struct drm_i915_private *dev_priv,
+void intel_flush_display_plane(struct drm_i915_private *dev_priv,
 				      enum plane plane)
 {
 	I915_WRITE(DSPADDR(plane), I915_READ(DSPADDR(plane)));
@@ -6351,359 +6351,6 @@ static const struct drm_mode_config_funcs intel_mode_funcs = {
 	.output_poll_changed = intel_fb_output_poll_changed,
 };
 
-static void ironlake_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
-
-	/* Required for FBC */
-	dspclk_gate |= DPFCUNIT_CLOCK_GATE_DISABLE |
-		DPFCRUNIT_CLOCK_GATE_DISABLE |
-		DPFDUNIT_CLOCK_GATE_DISABLE;
-	/* Required for CxSR */
-	dspclk_gate |= DPARBUNIT_CLOCK_GATE_DISABLE;
-
-	I915_WRITE(PCH_3DCGDIS0,
-		   MARIUNIT_CLOCK_GATE_DISABLE |
-		   SVSMUNIT_CLOCK_GATE_DISABLE);
-	I915_WRITE(PCH_3DCGDIS1,
-		   VFMUNIT_CLOCK_GATE_DISABLE);
-
-	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
-
-	/*
-	 * According to the spec the following bits should be set in
-	 * order to enable memory self-refresh
-	 * The bit 22/21 of 0x42004
-	 * The bit 5 of 0x42020
-	 * The bit 15 of 0x45000
-	 */
-	I915_WRITE(ILK_DISPLAY_CHICKEN2,
-		   (I915_READ(ILK_DISPLAY_CHICKEN2) |
-		    ILK_DPARB_GATE | ILK_VSDPFD_FULL));
-	I915_WRITE(ILK_DSPCLK_GATE,
-		   (I915_READ(ILK_DSPCLK_GATE) |
-		    ILK_DPARB_CLK_GATE));
-	I915_WRITE(DISP_ARB_CTL,
-		   (I915_READ(DISP_ARB_CTL) |
-		    DISP_FBC_WM_DIS));
-	I915_WRITE(WM3_LP_ILK, 0);
-	I915_WRITE(WM2_LP_ILK, 0);
-	I915_WRITE(WM1_LP_ILK, 0);
-
-	/*
-	 * Based on the document from hardware guys the following bits
-	 * should be set unconditionally in order to enable FBC.
-	 * The bit 22 of 0x42000
-	 * The bit 22 of 0x42004
-	 * The bit 7,8,9 of 0x42020.
-	 */
-	if (IS_IRONLAKE_M(dev)) {
-		I915_WRITE(ILK_DISPLAY_CHICKEN1,
-			   I915_READ(ILK_DISPLAY_CHICKEN1) |
-			   ILK_FBCQ_DIS);
-		I915_WRITE(ILK_DISPLAY_CHICKEN2,
-			   I915_READ(ILK_DISPLAY_CHICKEN2) |
-			   ILK_DPARB_GATE);
-		I915_WRITE(ILK_DSPCLK_GATE,
-			   I915_READ(ILK_DSPCLK_GATE) |
-			   ILK_DPFC_DIS1 |
-			   ILK_DPFC_DIS2 |
-			   ILK_CLK_FBC);
-	}
-
-	I915_WRITE(ILK_DISPLAY_CHICKEN2,
-		   I915_READ(ILK_DISPLAY_CHICKEN2) |
-		   ILK_ELPIN_409_SELECT);
-	I915_WRITE(_3D_CHICKEN2,
-		   _3D_CHICKEN2_WM_READ_PIPELINED << 16 |
-		   _3D_CHICKEN2_WM_READ_PIPELINED);
-}
-
-static void gen6_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe;
-	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
-
-	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
-
-	I915_WRITE(ILK_DISPLAY_CHICKEN2,
-		   I915_READ(ILK_DISPLAY_CHICKEN2) |
-		   ILK_ELPIN_409_SELECT);
-
-	I915_WRITE(WM3_LP_ILK, 0);
-	I915_WRITE(WM2_LP_ILK, 0);
-	I915_WRITE(WM1_LP_ILK, 0);
-
-	/* clear masked bit */
-	I915_WRITE(CACHE_MODE_0,
-		   CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT);
-
-	I915_WRITE(GEN6_UCGCTL1,
-		   I915_READ(GEN6_UCGCTL1) |
-		   GEN6_BLBUNIT_CLOCK_GATE_DISABLE |
-		   GEN6_CSUNIT_CLOCK_GATE_DISABLE);
-
-	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
-	 * gating disable must be set.  Failure to set it results in
-	 * flickering pixels due to Z write ordering failures after
-	 * some amount of runtime in the Mesa "fire" demo, and Unigine
-	 * Sanctuary and Tropics, and apparently anything else with
-	 * alpha test or pixel discard.
-	 *
-	 * According to the spec, bit 11 (RCCUNIT) must also be set,
-	 * but we didn't debug actual testcases to find it out.
-	 */
-	I915_WRITE(GEN6_UCGCTL2,
-		   GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
-		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);
-
-	/* Bspec says we need to always set all mask bits. */
-	I915_WRITE(_3D_CHICKEN, (0xFFFF << 16) |
-		   _3D_CHICKEN_SF_DISABLE_FASTCLIP_CULL);
-
-	/*
-	 * According to the spec the following bits should be
-	 * set in order to enable memory self-refresh and fbc:
-	 * The bit21 and bit22 of 0x42000
-	 * The bit21 and bit22 of 0x42004
-	 * The bit5 and bit7 of 0x42020
-	 * The bit14 of 0x70180
-	 * The bit14 of 0x71180
-	 */
-	I915_WRITE(ILK_DISPLAY_CHICKEN1,
-		   I915_READ(ILK_DISPLAY_CHICKEN1) |
-		   ILK_FBCQ_DIS | ILK_PABSTRETCH_DIS);
-	I915_WRITE(ILK_DISPLAY_CHICKEN2,
-		   I915_READ(ILK_DISPLAY_CHICKEN2) |
-		   ILK_DPARB_GATE | ILK_VSDPFD_FULL);
-	I915_WRITE(ILK_DSPCLK_GATE,
-		   I915_READ(ILK_DSPCLK_GATE) |
-		   ILK_DPARB_CLK_GATE  |
-		   ILK_DPFD_CLK_GATE);
-
-	for_each_pipe(pipe) {
-		I915_WRITE(DSPCNTR(pipe),
-			   I915_READ(DSPCNTR(pipe)) |
-			   DISPPLANE_TRICKLE_FEED_DISABLE);
-		intel_flush_display_plane(dev_priv, pipe);
-	}
-}
-
-static void gen7_setup_fixed_func_scheduler(struct drm_i915_private *dev_priv)
-{
-	uint32_t reg = I915_READ(GEN7_FF_THREAD_MODE);
-
-	reg &= ~GEN7_FF_SCHED_MASK;
-	reg |= GEN7_FF_TS_SCHED_HW;
-	reg |= GEN7_FF_VS_SCHED_HW;
-	reg |= GEN7_FF_DS_SCHED_HW;
-
-	I915_WRITE(GEN7_FF_THREAD_MODE, reg);
-}
-
-static void ivybridge_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe;
-	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
-
-	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
-
-	I915_WRITE(WM3_LP_ILK, 0);
-	I915_WRITE(WM2_LP_ILK, 0);
-	I915_WRITE(WM1_LP_ILK, 0);
-
-	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
-	 * This implements the WaDisableRCZUnitClockGating workaround.
-	 */
-	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);
-
-	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);
-
-	I915_WRITE(IVB_CHICKEN3,
-		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
-		   CHICKEN3_DGMG_DONE_FIX_DISABLE);
-
-	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
-	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
-		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
-
-	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
-	I915_WRITE(GEN7_L3CNTLREG1,
-			GEN7_WA_FOR_GEN7_L3_CONTROL);
-	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER,
-			GEN7_WA_L3_CHICKEN_MODE);
-
-	/* This is required by WaCatErrorRejectionIssue */
-	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
-			I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
-			GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);
-
-	for_each_pipe(pipe) {
-		I915_WRITE(DSPCNTR(pipe),
-			   I915_READ(DSPCNTR(pipe)) |
-			   DISPPLANE_TRICKLE_FEED_DISABLE);
-		intel_flush_display_plane(dev_priv, pipe);
-	}
-
-	gen7_setup_fixed_func_scheduler(dev_priv);
-}
-
-static void valleyview_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe;
-	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
-
-	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
-
-	I915_WRITE(WM3_LP_ILK, 0);
-	I915_WRITE(WM2_LP_ILK, 0);
-	I915_WRITE(WM1_LP_ILK, 0);
-
-	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
-	 * This implements the WaDisableRCZUnitClockGating workaround.
-	 */
-	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);
-
-	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);
-
-	I915_WRITE(IVB_CHICKEN3,
-		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
-		   CHICKEN3_DGMG_DONE_FIX_DISABLE);
-
-	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
-	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
-		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
-
-	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
-	I915_WRITE(GEN7_L3CNTLREG1, GEN7_WA_FOR_GEN7_L3_CONTROL);
-	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER, GEN7_WA_L3_CHICKEN_MODE);
-
-	/* This is required by WaCatErrorRejectionIssue */
-	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
-		   I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
-		   GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);
-
-	for_each_pipe(pipe) {
-		I915_WRITE(DSPCNTR(pipe),
-			   I915_READ(DSPCNTR(pipe)) |
-			   DISPPLANE_TRICKLE_FEED_DISABLE);
-		intel_flush_display_plane(dev_priv, pipe);
-	}
-
-	I915_WRITE(CACHE_MODE_1, I915_READ(CACHE_MODE_1) |
-		   (PIXEL_SUBSPAN_COLLECT_OPT_DISABLE << 16) |
-		   PIXEL_SUBSPAN_COLLECT_OPT_DISABLE);
-}
-
-static void g4x_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	uint32_t dspclk_gate;
-
-	I915_WRITE(RENCLK_GATE_D1, 0);
-	I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
-		   GS_UNIT_CLOCK_GATE_DISABLE |
-		   CL_UNIT_CLOCK_GATE_DISABLE);
-	I915_WRITE(RAMCLK_GATE_D, 0);
-	dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE |
-		OVRUNIT_CLOCK_GATE_DISABLE |
-		OVCUNIT_CLOCK_GATE_DISABLE;
-	if (IS_GM45(dev))
-		dspclk_gate |= DSSUNIT_CLOCK_GATE_DISABLE;
-	I915_WRITE(DSPCLK_GATE_D, dspclk_gate);
-}
-
-static void crestline_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	I915_WRITE(RENCLK_GATE_D1, I965_RCC_CLOCK_GATE_DISABLE);
-	I915_WRITE(RENCLK_GATE_D2, 0);
-	I915_WRITE(DSPCLK_GATE_D, 0);
-	I915_WRITE(RAMCLK_GATE_D, 0);
-	I915_WRITE16(DEUC, 0);
-}
-
-static void broadwater_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	I915_WRITE(RENCLK_GATE_D1, I965_RCZ_CLOCK_GATE_DISABLE |
-		   I965_RCC_CLOCK_GATE_DISABLE |
-		   I965_RCPB_CLOCK_GATE_DISABLE |
-		   I965_ISC_CLOCK_GATE_DISABLE |
-		   I965_FBC_CLOCK_GATE_DISABLE);
-	I915_WRITE(RENCLK_GATE_D2, 0);
-}
-
-static void gen3_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	u32 dstate = I915_READ(D_STATE);
-
-	dstate |= DSTATE_PLL_D3_OFF | DSTATE_GFX_CLOCK_GATING |
-		DSTATE_DOT_CLOCK_GATING;
-	I915_WRITE(D_STATE, dstate);
-}
-
-static void i85x_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE);
-}
-
-static void i830_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
-}
-
-static void ibx_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	/*
-	 * On Ibex Peak and Cougar Point, we need to disable clock
-	 * gating for the panel power sequencer or it will fail to
-	 * start up when no ports are active.
-	 */
-	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
-}
-
-static void cpt_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe;
-
-	/*
-	 * On Ibex Peak and Cougar Point, we need to disable clock
-	 * gating for the panel power sequencer or it will fail to
-	 * start up when no ports are active.
-	 */
-	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
-	I915_WRITE(SOUTH_CHICKEN2, I915_READ(SOUTH_CHICKEN2) |
-		   DPLS_EDP_PPS_FIX_DIS);
-	/* Without this, mode sets may fail silently on FDI */
-	for_each_pipe(pipe)
-		I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_AUTOTRAIN_GEN_STALL_DIS);
-}
-
-void intel_init_clock_gating(struct drm_device *dev)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-
-	dev_priv->display.init_clock_gating(dev);
-
-	if (dev_priv->display.init_pch_clock_gating)
-		dev_priv->display.init_pch_clock_gating(dev);
-}
-
 /* Set up chip specific display functions */
 static void intel_init_display(struct drm_device *dev)
 {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index c87f29a..771075c 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -339,6 +339,8 @@ extern bool intel_dpd_is_edp(struct drm_device *dev);
 extern void intel_edp_link_config(struct intel_encoder *, int *, int *);
 extern bool intel_encoder_is_pch_edp(struct drm_encoder *encoder);
 extern int intel_plane_init(struct drm_device *dev, enum pipe pipe);
+extern void intel_flush_display_plane(struct drm_i915_private *dev_priv,
+				      enum plane plane);
 
 /* intel_panel.c */
 extern void intel_fixed_panel_mode(struct drm_display_mode *fixed_mode,
@@ -490,4 +492,18 @@ extern int i85x_get_fifo_size(struct drm_device *dev, int plane);
 extern int i845_get_fifo_size(struct drm_device *dev, int plane);
 extern int i830_get_fifo_size(struct drm_device *dev, int plane);
 
+/* Clock gating */
+extern void ironlake_init_clock_gating(struct drm_device *dev);
+extern void gen6_init_clock_gating(struct drm_device *dev);
+extern void ivybridge_init_clock_gating(struct drm_device *dev);
+extern void valleyview_init_clock_gating(struct drm_device *dev);
+extern void g4x_init_clock_gating(struct drm_device *dev);
+extern void crestline_init_clock_gating(struct drm_device *dev);
+extern void broadwater_init_clock_gating(struct drm_device *dev);
+extern void gen3_init_clock_gating(struct drm_device *dev);
+extern void i85x_init_clock_gating(struct drm_device *dev);
+extern void i830_init_clock_gating(struct drm_device *dev);
+extern void ibx_init_clock_gating(struct drm_device *dev);
+extern void cpt_init_clock_gating(struct drm_device *dev);
+
 #endif /* __INTEL_DRV_H__ */
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 832130e..4f35df2 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2578,3 +2578,356 @@ void intel_init_emon(struct drm_device *dev)
 	dev_priv->corr = (lcfuse & LCFUSE_HIV_MASK);
 }
 
+void ironlake_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
+
+	/* Required for FBC */
+	dspclk_gate |= DPFCUNIT_CLOCK_GATE_DISABLE |
+		DPFCRUNIT_CLOCK_GATE_DISABLE |
+		DPFDUNIT_CLOCK_GATE_DISABLE;
+	/* Required for CxSR */
+	dspclk_gate |= DPARBUNIT_CLOCK_GATE_DISABLE;
+
+	I915_WRITE(PCH_3DCGDIS0,
+		   MARIUNIT_CLOCK_GATE_DISABLE |
+		   SVSMUNIT_CLOCK_GATE_DISABLE);
+	I915_WRITE(PCH_3DCGDIS1,
+		   VFMUNIT_CLOCK_GATE_DISABLE);
+
+	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
+
+	/*
+	 * According to the spec the following bits should be set in
+	 * order to enable memory self-refresh
+	 * The bit 22/21 of 0x42004
+	 * The bit 5 of 0x42020
+	 * The bit 15 of 0x45000
+	 */
+	I915_WRITE(ILK_DISPLAY_CHICKEN2,
+		   (I915_READ(ILK_DISPLAY_CHICKEN2) |
+		    ILK_DPARB_GATE | ILK_VSDPFD_FULL));
+	I915_WRITE(ILK_DSPCLK_GATE,
+		   (I915_READ(ILK_DSPCLK_GATE) |
+		    ILK_DPARB_CLK_GATE));
+	I915_WRITE(DISP_ARB_CTL,
+		   (I915_READ(DISP_ARB_CTL) |
+		    DISP_FBC_WM_DIS));
+	I915_WRITE(WM3_LP_ILK, 0);
+	I915_WRITE(WM2_LP_ILK, 0);
+	I915_WRITE(WM1_LP_ILK, 0);
+
+	/*
+	 * Based on the document from hardware guys the following bits
+	 * should be set unconditionally in order to enable FBC.
+	 * The bit 22 of 0x42000
+	 * The bit 22 of 0x42004
+	 * The bit 7,8,9 of 0x42020.
+	 */
+	if (IS_IRONLAKE_M(dev)) {
+		I915_WRITE(ILK_DISPLAY_CHICKEN1,
+			   I915_READ(ILK_DISPLAY_CHICKEN1) |
+			   ILK_FBCQ_DIS);
+		I915_WRITE(ILK_DISPLAY_CHICKEN2,
+			   I915_READ(ILK_DISPLAY_CHICKEN2) |
+			   ILK_DPARB_GATE);
+		I915_WRITE(ILK_DSPCLK_GATE,
+			   I915_READ(ILK_DSPCLK_GATE) |
+			   ILK_DPFC_DIS1 |
+			   ILK_DPFC_DIS2 |
+			   ILK_CLK_FBC);
+	}
+
+	I915_WRITE(ILK_DISPLAY_CHICKEN2,
+		   I915_READ(ILK_DISPLAY_CHICKEN2) |
+		   ILK_ELPIN_409_SELECT);
+	I915_WRITE(_3D_CHICKEN2,
+		   _3D_CHICKEN2_WM_READ_PIPELINED << 16 |
+		   _3D_CHICKEN2_WM_READ_PIPELINED);
+}
+
+void gen6_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int pipe;
+	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
+
+	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
+
+	I915_WRITE(ILK_DISPLAY_CHICKEN2,
+		   I915_READ(ILK_DISPLAY_CHICKEN2) |
+		   ILK_ELPIN_409_SELECT);
+
+	I915_WRITE(WM3_LP_ILK, 0);
+	I915_WRITE(WM2_LP_ILK, 0);
+	I915_WRITE(WM1_LP_ILK, 0);
+
+	/* clear masked bit */
+	I915_WRITE(CACHE_MODE_0,
+		   CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT);
+
+	I915_WRITE(GEN6_UCGCTL1,
+		   I915_READ(GEN6_UCGCTL1) |
+		   GEN6_BLBUNIT_CLOCK_GATE_DISABLE |
+		   GEN6_CSUNIT_CLOCK_GATE_DISABLE);
+
+	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
+	 * gating disable must be set.  Failure to set it results in
+	 * flickering pixels due to Z write ordering failures after
+	 * some amount of runtime in the Mesa "fire" demo, and Unigine
+	 * Sanctuary and Tropics, and apparently anything else with
+	 * alpha test or pixel discard.
+	 *
+	 * According to the spec, bit 11 (RCCUNIT) must also be set,
+	 * but we didn't debug actual testcases to find it out.
+	 */
+	I915_WRITE(GEN6_UCGCTL2,
+		   GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
+		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);
+
+	/* Bspec says we need to always set all mask bits. */
+	I915_WRITE(_3D_CHICKEN, (0xFFFF << 16) |
+		   _3D_CHICKEN_SF_DISABLE_FASTCLIP_CULL);
+
+	/*
+	 * According to the spec the following bits should be
+	 * set in order to enable memory self-refresh and fbc:
+	 * The bit21 and bit22 of 0x42000
+	 * The bit21 and bit22 of 0x42004
+	 * The bit5 and bit7 of 0x42020
+	 * The bit14 of 0x70180
+	 * The bit14 of 0x71180
+	 */
+	I915_WRITE(ILK_DISPLAY_CHICKEN1,
+		   I915_READ(ILK_DISPLAY_CHICKEN1) |
+		   ILK_FBCQ_DIS | ILK_PABSTRETCH_DIS);
+	I915_WRITE(ILK_DISPLAY_CHICKEN2,
+		   I915_READ(ILK_DISPLAY_CHICKEN2) |
+		   ILK_DPARB_GATE | ILK_VSDPFD_FULL);
+	I915_WRITE(ILK_DSPCLK_GATE,
+		   I915_READ(ILK_DSPCLK_GATE) |
+		   ILK_DPARB_CLK_GATE  |
+		   ILK_DPFD_CLK_GATE);
+
+	for_each_pipe(pipe) {
+		I915_WRITE(DSPCNTR(pipe),
+			   I915_READ(DSPCNTR(pipe)) |
+			   DISPPLANE_TRICKLE_FEED_DISABLE);
+		intel_flush_display_plane(dev_priv, pipe);
+	}
+}
+
+static void gen7_setup_fixed_func_scheduler(struct drm_i915_private *dev_priv)
+{
+	uint32_t reg = I915_READ(GEN7_FF_THREAD_MODE);
+
+	reg &= ~GEN7_FF_SCHED_MASK;
+	reg |= GEN7_FF_TS_SCHED_HW;
+	reg |= GEN7_FF_VS_SCHED_HW;
+	reg |= GEN7_FF_DS_SCHED_HW;
+
+	I915_WRITE(GEN7_FF_THREAD_MODE, reg);
+}
+
+void ivybridge_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int pipe;
+	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
+
+	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
+
+	I915_WRITE(WM3_LP_ILK, 0);
+	I915_WRITE(WM2_LP_ILK, 0);
+	I915_WRITE(WM1_LP_ILK, 0);
+
+	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
+	 * This implements the WaDisableRCZUnitClockGating workaround.
+	 */
+	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);
+
+	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);
+
+	I915_WRITE(IVB_CHICKEN3,
+		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
+		   CHICKEN3_DGMG_DONE_FIX_DISABLE);
+
+	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
+	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
+		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
+
+	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
+	I915_WRITE(GEN7_L3CNTLREG1,
+			GEN7_WA_FOR_GEN7_L3_CONTROL);
+	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER,
+			GEN7_WA_L3_CHICKEN_MODE);
+
+	/* This is required by WaCatErrorRejectionIssue */
+	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
+			I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
+			GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);
+
+	for_each_pipe(pipe) {
+		I915_WRITE(DSPCNTR(pipe),
+			   I915_READ(DSPCNTR(pipe)) |
+			   DISPPLANE_TRICKLE_FEED_DISABLE);
+		intel_flush_display_plane(dev_priv, pipe);
+	}
+
+	gen7_setup_fixed_func_scheduler(dev_priv);
+}
+
+void valleyview_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int pipe;
+	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
+
+	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);
+
+	I915_WRITE(WM3_LP_ILK, 0);
+	I915_WRITE(WM2_LP_ILK, 0);
+	I915_WRITE(WM1_LP_ILK, 0);
+
+	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
+	 * This implements the WaDisableRCZUnitClockGating workaround.
+	 */
+	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);
+
+	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);
+
+	I915_WRITE(IVB_CHICKEN3,
+		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
+		   CHICKEN3_DGMG_DONE_FIX_DISABLE);
+
+	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
+	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
+		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
+
+	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
+	I915_WRITE(GEN7_L3CNTLREG1, GEN7_WA_FOR_GEN7_L3_CONTROL);
+	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER, GEN7_WA_L3_CHICKEN_MODE);
+
+	/* This is required by WaCatErrorRejectionIssue */
+	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
+		   I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
+		   GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);
+
+	for_each_pipe(pipe) {
+		I915_WRITE(DSPCNTR(pipe),
+			   I915_READ(DSPCNTR(pipe)) |
+			   DISPPLANE_TRICKLE_FEED_DISABLE);
+		intel_flush_display_plane(dev_priv, pipe);
+	}
+
+	I915_WRITE(CACHE_MODE_1, I915_READ(CACHE_MODE_1) |
+		   (PIXEL_SUBSPAN_COLLECT_OPT_DISABLE << 16) |
+		   PIXEL_SUBSPAN_COLLECT_OPT_DISABLE);
+}
+
+void g4x_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	uint32_t dspclk_gate;
+
+	I915_WRITE(RENCLK_GATE_D1, 0);
+	I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
+		   GS_UNIT_CLOCK_GATE_DISABLE |
+		   CL_UNIT_CLOCK_GATE_DISABLE);
+	I915_WRITE(RAMCLK_GATE_D, 0);
+	dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE |
+		OVRUNIT_CLOCK_GATE_DISABLE |
+		OVCUNIT_CLOCK_GATE_DISABLE;
+	if (IS_GM45(dev))
+		dspclk_gate |= DSSUNIT_CLOCK_GATE_DISABLE;
+	I915_WRITE(DSPCLK_GATE_D, dspclk_gate);
+}
+
+void crestline_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	I915_WRITE(RENCLK_GATE_D1, I965_RCC_CLOCK_GATE_DISABLE);
+	I915_WRITE(RENCLK_GATE_D2, 0);
+	I915_WRITE(DSPCLK_GATE_D, 0);
+	I915_WRITE(RAMCLK_GATE_D, 0);
+	I915_WRITE16(DEUC, 0);
+}
+
+void broadwater_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	I915_WRITE(RENCLK_GATE_D1, I965_RCZ_CLOCK_GATE_DISABLE |
+		   I965_RCC_CLOCK_GATE_DISABLE |
+		   I965_RCPB_CLOCK_GATE_DISABLE |
+		   I965_ISC_CLOCK_GATE_DISABLE |
+		   I965_FBC_CLOCK_GATE_DISABLE);
+	I915_WRITE(RENCLK_GATE_D2, 0);
+}
+
+void gen3_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 dstate = I915_READ(D_STATE);
+
+	dstate |= DSTATE_PLL_D3_OFF | DSTATE_GFX_CLOCK_GATING |
+		DSTATE_DOT_CLOCK_GATING;
+	I915_WRITE(D_STATE, dstate);
+}
+
+void i85x_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE);
+}
+
+void i830_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
+}
+
+void ibx_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	/*
+	 * On Ibex Peak and Cougar Point, we need to disable clock
+	 * gating for the panel power sequencer or it will fail to
+	 * start up when no ports are active.
+	 */
+	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
+}
+
+void cpt_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int pipe;
+
+	/*
+	 * On Ibex Peak and Cougar Point, we need to disable clock
+	 * gating for the panel power sequencer or it will fail to
+	 * start up when no ports are active.
+	 */
+	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
+	I915_WRITE(SOUTH_CHICKEN2, I915_READ(SOUTH_CHICKEN2) |
+		   DPLS_EDP_PPS_FIX_DIS);
+	/* Without this, mode sets may fail silently on FDI */
+	for_each_pipe(pipe)
+		I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_AUTOTRAIN_GEN_STALL_DIS);
+}
+
+void intel_init_clock_gating(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	dev_priv->display.init_clock_gating(dev);
+
+	if (dev_priv->display.init_pch_clock_gating)
+		dev_priv->display.init_pch_clock_gating(dev);
+}
+